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Since Im upgrading to 440cc injectors I would like to control them with something. IIRC the SAFC can only control the MY00+ during WOT (closed-loop I believe). If I'm wrong PLEASE correct me. What I was looking at was the Split Second ARC2. I did a search and found 3 threads that didnt help at all. The ARC2's specs and everything can be seen here:http://www.splitsec.com/products/arc2/arc2ds.htm

SplitSec's overview of the product is as follows:

Quote:

The ARC2 (Air/fuel Ratio Calibrator) provides additional features over the ARC1. These features make it possible to fit a MAF sensor to engines that were designed to operate with vane type air flow meters. It is especially useful for re-calibration of modified engines that have ECU (Engine Control Units) designed for MAP or MAF (Mass Air Flow) sensors, also compatible with GM and Karman Vortex applications. In addition to the low and high load adjustments of the ARC1, the ARC2 also provides adjustments for mid load and acceleration boost

It sounds like it should work fine with our MAPs but I'm wondering if it would only work during WOT as well.

And obviously I would want to organize a group buy because of the price. I was also looking at a TMC1. It would be great if we could get a group buy on both pieces going. But first lets discuss the ARC2 and if it would work properly or not.

i think it acts as a voltage clamp as well. he said it has a map within it that sends a signal. if i ****ed up please tell me so i can call them back and ask them some more questions and/or cancel my order.

allright, he recommended the ARC1-002 I think was the part number. The person you spoke to wasn't available (Mark), but he's going to call me back so I can pry as much info as possible from him. He said the ARC1-002 has a boost input.

the model number he ordered for me isnt on their site. i think he ordered me the same one Jewbaru is talking about. Its also more expensive (~320). and about the vacuum, i was thinking the same thing you are. he made it sound like there wouldnt be a problem. I hope Mark calls you back.

I talked to Mark a little while ago, I just recently got a chance to post, here's the scoop.

The ARC1-002 works like this:

There are two knobs, a low, and a high kindof like how the regular unit is, BUT the knobs work differently.

The low knob only works in the minus, so you use it to dial back the mixture if you're running overly rich off boost (like most 2000 owners are). This works up till 0 vacuum. The ARC also has a built in MAP sensor, so when it sees positive pressure, the high knob kicks in. With it, you can adjust fuel delivery, and enrichen/lean out the mixture as needed.

Aside from this, the ARC1-002 has a built in clamp, and it can be set to whatever we'd like.

Now, in order for the ARC1-002 to work at it's full potential, you'd still need to increase fuel pressure when the car is on boost. Upping the fuel pressure a bit, then using the ARC to fine tune it will yeild the best results.

Andrew, I'm gonna e-mail you with some more details and such. I want to be sure to stay in close contact with you in regards to the tuning and such. This sounds like it could be a reliable alternative to the more expensive full engine managment for those who are looking to run reliable low boost.

i don't quite understand how this unit works to control fuel after the voltage clamp kicks in. does it control the injectors directly? i seem to be missing something here. anyone have any details on how this unit works with the stock ecu?

ok, basically, it "scales" the voltage down depending on your settings.

Say N/A at a certain vacuum point, the ECU was seeing 2.8v and adjusting fuel accordingly. What the ARC would do is take that voltage coming in and scale it. So if N/A you saw 2.8v, with the ARC tuned you might see 1.8v.

What this would do is offset the car's running rich with a high flow fuel pump, and at the same time give a smooth rise in fuel delivery. The only time it would "clamp" is if you had the HIGH knob turned high enough to where it would max out the voltage at a certain PSI.

It intercepts the MAP signal from the sensor, and alters it for the ECU, never going over a set voltage.